Comparative Research into the Application of Pulsating Current in the Conservation of Iron Artefacts

Rad donosi teorijsko-eksperimentalnu analizu i komparativno istraživanje metode ekstrakcije klorida pulsirajućom strujom. Kao komparabilne metode korištene su dvije najprimjenjivanije metode ekstrakcije klorida: ekstrakcija lužnatom sulfitnom otopinom i elektrolitska redukcija sa stalnim naponom. Cilj je rada verifikacija dosadašnjih saznanja i rezultata istraživanja pulsirajuće struje, istraživanje mogućnosti, prilagodbi i razvoja opreme te analiza rezultata njezine primjene na stvarnim željeznim arheološkim artefaktima, u konzervatorski prihvatljivim uvjetima.The paper presents a theoretical and experimental analysis and a comparative research into the method of extracting chlorides by pulsating current, the effects and application possibilities of which are compared with the extraction by alkaline sulfite solution and electrolytic reduction in potentiostatic mode. The paper aims to verify present knowledge and results of research into pulsating current done on artificially oxidized and chloridized iron, as well as to research into the possibilities and results of its application in actual conservation-appropriate circumstances. Considering that the relative unavailability and high price of the specialized equipment needed for the research and application of pulsating current is one of the reasons for its lesser popularity and insight into it, this paper also features a schematic circuit diagram and explication of the principle by which the electronic variable frequency and duty cycle generator of pulsating current operates. For the purposes of research it was created by the author of this paper, thus allowing every interested researcher or conservator who wishes to continue researching this method or initiate its practical application to easily follow suit. By comparing procedures and results with the two most often used methods of extracting chlorides, and also with the results of previous research, the paper presents the advantages but also potential shortcomings, i.e. dangers of applying those methods